It is known that a sounding board for a piano is generally made of a plank or wood panel, for example of fir wood with a thickness of about 10 mm, the configuration of which essentially corresponds seen from above to the shape of the piano (as shown in FIG. 1 with regard to a grand piano).
Such boards or panels are usually made from a plurality of wooden planks laid side by side and attached to each other along their respective sides. The planks of the sounding board, as is well known, are cut from a respective wooden trunk, so that in each plank the upper face and the lower face either have longitudinal veins (with technical term called “bacon”) parallel to each other and parallel to the sides of the planks, or in other words, perpendicular to the plane delimited by the head and tail face of the plank (see FIG. 2, showing one among a plurality of available cutting methods).
In a traditional sounding board, each plank has a width of about 8-12 cm, a thickness of 10 mm and a different length depending on the position it takes in the sounding board.
To make a sounding board the planks of the plurality of planks are laid side by side at their respective longitudinal sides, and are bound together using a suitable adhesive material. Then they are cut in order to take a diagonal or “angled” direction with respect to the sounding board itself, as shown in FIG. 3.
Now, the board so obtained has a good bending strength in the direction of the veins of the respective planks, but has a low bending strength along a direction perpendicular to the same, for which reason the application is necessary, by an adhesive, of a plurality of cross elements, (in technical term also called “ribs” or “chains”) which are fastened to the lower face of the sounding board and are laid parallel one to another and perpendicular to the direction of the veins of the planks of the same (FIG. 4).
Traditional sounding boards suffer from many drawbacks.
First of all, in the course of time, cracks of the sounding board are found along the veins of the planks from which it is made. This is due to the natural drying of the wooden fibers making up the planks of the sounding board, which in the course of time are reduced in volume to a greater extent along the direction perpendicular to the veins, which causes in the same direction the loss of compression of the sounding board.
In general other factors also affect the occurrence of such cracks, among which:                the type of adhesive used for gluing the planks, for applying the cross elements or chains on the sounding board and for applying to the board other components of the piano as, for instance, the bridges;        the fact that the sounding board itself is bound at its peripheral ends to the structure of the piano, and as is known, it is kept compressed by the strings of the piano;        the kind and quality of wood used to make the planks that make up the sounding board;        the irregularities of the planks themselves, the profile of which could not be perfectly linear.        
This drawback due to the cracks of the sounding board occurs in the course of time, to a greater extent in Countries characterized by a cold and dry climate and, in general, in environments with under-floor heating.
The cracks can obviously limit the function of the piano reducing its value, not to mention their repairs, in addition to being onerous from the economic point of view, and require long and laborious operations to remove the strings and the frame of cast iron from the sounding board and their subsequent replacement, once having completed the repairs.
Main aim of the present invention is therefore to provide a sounding board for musical instruments in which the likelihood of the occurrence of cracks of the same is set to zero or at least is greatly reduced.
Another aim of the present invention is to provide a sounding board for musical instruments which is less sensitive to the climate changes with respect to the traditional sounding boards.
Further aim of the present invention is to provide a sounding board for musical instruments the quality of which is greater than that of the traditional sounding boards.
Not least aim of the present invention is to provide a method of assembling a sounding board for musical instruments which is easy to implement.